U.S. DAMS: IS SECURITY SEEPING THROUGH THE CRACKS

The complex watershed of North America should be considered a critical component of its infrastructure — and is therefore a potential terrorist target. In some cases, dams provide energy, supply drinking water and enable sporting and recreational opportunities. Currently, there are nearly 80,000 dams in the national inventory, most of which are privately owned. Less than 3 percent of those dams are owned by the Federal Government.

In 2003, there were 10,049 dams that were considered “high hazard,” or dams that are located where a city is less than one mile downstream, according to the American Society of Civil Engineers (ASCE). The ASCE also published that the United States has identified 2,600 dams as “unsafe.” In the past few years more than 520 dam incidents, including 21 dam failures, were reported to the National Performance of Dams Program. Dams, like all structures, deteriorate over time and require inspection and maintenance.

While much attention has been given to large dams, little attention has been given to smaller structures such as earthen dams, which comprise the vast majority of dams in the national inventory. Earthen dams, also called earth dams or earth-fill dams, are constructed as a simple embankment of well-compacted earth, sometimes with a water-tight concrete or clay core or upstream face, or with a hydraulic fill to produce a watertight core.

Embankment dams also fall into this classification of dams. They are made from fill material not joined by mortar and have two main types — rockfill and earth dams. Embankment dams rely on their weight to hold back water, like gravity dams made from concrete. The head wall of the dam or the embankment of the dam is what holds back the water.

It is here where the greatest vulnerability for a terrorist attack exists. Earthen dams are prime targets for a terrorist attack for several reasons: They are in remote areas often out of public view; a typical head wall would be no match for conventional explosives; an attack on a “high hazard dam” in the middle of the night could cause hundreds if not a few thousand deaths; and the economical and psychological impact of breaching one of these dams would be significant.

Given that most of these dams are privately owned and that federal, state and local authorities therefore have limited regulatory authority (other than inspection), there are no mandated security measures against terrorism. So the big question is — who is responsible for securing these dams? The answer is — no one! They have fallen into the “white space” between federal, state and local authorities.

How vulnerable are they? One earthen dam in West Virginia has deployed merely a high-security chain and padlock to secure the dual gates to the road. The chain is the only thing stopping a moderately-sized truck from driving right up to the base of the headwall. Although there are more than 100 homes and buildings within a mile of the dam, the location is obscure and not visible but to a single home. An Oklahoma City-type truck bomb exploding near the middle of the headwall would likely breach a small portion, and the water pressure behind the wall would do the rest.

The Journal of the International Association of Counter-Terrorism and Security Professionals (IACSP) recently published a scenario planning methodology that evaluated a terrorist attack or attacks on small earthen high hazard dams. The report finds:

The consequences of a terrorist attack on a dam could be catastrophic — even the small earthen dams. Multiple simultaneous attacks on two or three of these structures could create mass casualties on a scale greater than on Sept. 11, 2001. Numerous federal and state agencies have conducted or planned risk assessments.

There are a number of physical security sensors and systems that can be put in place to alert the authorities in real-time to vehicles or individuals on or around the dam, but the purchase and installation of these systems would be costly. Who is responsible for providing proper security? Where does the owners’ responsibility end? With multiple federal agencies sharing some responsibility for these structures, who will be the coordinating agency?

A 100-year-old timber dam in Taunton, Mass. is overstressed and in danger of breaking. While the threat was created by a natural event, the question of who is responsible for risk management of these structures is still unclear.

It is impossible to mitigate all risks of terrorist attack. One needs to focus on targets where terrorist would have a high likelihood of success, a minimal likelihood of detection and fair degree of psychological and economic impact. With the dam in Taunton, Mass., there is a chance to plan ahead and look into who is responsible. In the case of a terrorist attack, dam officials must get the protection systems in place before it is too late.

ABOUT THE AUTHOR

Kevin G. Coleman writes for Technolytics and has regularly featured articles in Directions Magazine and International Intelligence magazine covering terrorism, security and intelligence worldwide. He is a strategic advisor with a leading U.S. research institution that serves Department of Defense, Homeland Security and the Intelligence community.

U.S. DAMS: FAST FACTS